Scientists hope to gain new information about salmon migration patterns now that an in-depth study is back on track.
Researchers at Oregon State University had to put their efforts on hold for the past two years. That's because most salmon fishing was restricted along the west coast.
The goal of the research is to more accurately pinpoint where salmon from specific rivers spend their time in the ocean.
OSU marine researcher Gil Sylvia says that could eventually mean fewer wide scale shutdowns of the salmon industry to protect endangered fish.
Gil Sylvia: "The tendency right now is just to close large areas of the ocean. And that then froze the entire fleet off the water. So our goal here is to keep these guys on the water fishing but at the same time, protect and conserve weak stocks."
Fishing crews off the coasts of Oregon, California and Washington are collecting tissue samples of the chinook salmon they catch.
Sylvia says those samples allow researchers to determine within 90 percent accuracy which river the salmon came from.